Plumbing systems include multiple pipes connected via fittings to form a plumbing line. Plumbing lines for residential and commercial structures include water lines, vent lines and drain lines. Drain lines provide a conduit to discharge fluid and waste to sewer pipes or a sewer system. Plumbing lines including drain lines are tested prior to use to make sure there are no leaks in the system. For testing, the line and pipes are filled with air, water or other flowable medium to detect leaks. Typically, connection of the drain pipe to a sewer pipes or sewer line is sealed to test the drain line or system. The drain line is temporarily sealed by removing the pipe fitting connecting the drain pipe to the sewer pipe or line and capping the drain pipe above the sewer line or pipe. Once the line is tested, the cap is removed and the fitting is reconnected to join the drain pipe or line to the sewer pipe or line.